Entering the elderly man's home in Munich was described much like walking into a dump. Dirty plates and rotten food littered the floor.

But this was no waste site, reports the German magazine Focus. Among the trash hid some $1.3 billion in missing paintings, prints, and lithographs – including lost and unknown pieces from 20th century masters – some of which are believed to have been seized by Nazis ahead of World War II.

What's even more remarkable is that a collection of such value very well may never have been found – illustrating the sheer volume and complexity of ambiguous ownership of art around the globe.

It all started after an elderly man – who German authorities have not named, but severalmediaoutlets including Focus identify as Cornelius Gurlitt, son of late German art collector Hildebrand Gurlitt – was stopped in a routine check on a train from Zurich to Munich in 2010. He happened to have over $12,000 in cash.

While by law he was not required to declare the money, the man's activity raised suspicions of tax authorities, who inspected his apartment in February 2012 in an upscale area of Munich. They found 1,400 pieces, in a cupboard and drawers, in conditions that are considered “museum quality.”

Fast forward to this week: The art world is in a tizzy, and German officials are on the defense. Why has so much time lapsed between the discovery of the art and its public disclosure? Where is the man and how much of the art was legitimately acquired or not and by whom? How was his collection unknown to the system? And perhaps most important, what becomes of the art now?

Prosecutor Reinhard Nemetz told reporters Tuesday that they have "concrete evidence" that the trove includes pieces that were deemed “degenerate” by Nazis and seized from museums. According to Focus, 200 of the works found are the subject of international warrants.

Anne Webber, the co-chair of the Commission for Looted Art in Europe, says the story has "awoken a great hope” around the world. While it's unclear how much of this collection was looted, and that the whereabouts of the vast majority of such art remains unknown, her UK-based organization has received scores of calls from families with missing art, she says.

It's also created a buzz in the art world. As Meike Hoffmann, an expert in Berlin on "degenerate" works who is aiding the investigation, said today to reporters, "When you stand in front of the works, see the ones that were long thought to have been lost or destroyed and in a relatively good state – some of them dirty but not damaged – you have an incredible feeling of happiness," she told the Associated Press.